Send DLNA devices message to only the matched interface

This will be the right way for multiple interfaces, or the client will
receive all devices message with different IP addresses and could not
detect which one could access.

And provide one option DlnaOptions.SendOnlyMatchedHost to fallback to old
behaviour if this commit missed something.

1 files changed, 26 insertions, 4 deletions

diff --git a/RSSDP/SsdpDevicePublisher.cs b/RSSDP/SsdpDevicePublisher.cs
index ce64ba117..076246b24 100644
--- a/RSSDP/SsdpDevicePublisher.cs
+++ b/RSSDP/SsdpDevicePublisher.cs
@@ -7,6 +7,7 @@ using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using MediaBrowser.Model.Net;
+using MediaBrowser.Common.Net;
 using Rssdp;
 
 namespace Rssdp.Infrastructure
@@ -16,10 +17,12 @@ namespace Rssdp.Infrastructure
     /// </summary>
     public class SsdpDevicePublisher : DisposableManagedObjectBase, ISsdpDevicePublisher
     {
+        private readonly INetworkManager _networkManager;
 
         private ISsdpCommunicationsServer _CommsServer;
         private string _OSName;
         private string _OSVersion;
+        private bool _sendOnlyMatchedHost;
 
         private bool _SupportPnpRootDevice;
 
@@ -37,9 +40,11 @@ namespace Rssdp.Infrastructure
         /// <summary>
         /// Default constructor.
         /// </summary>
-        public SsdpDevicePublisher(ISsdpCommunicationsServer communicationsServer, string osName, string osVersion)
+        public SsdpDevicePublisher(ISsdpCommunicationsServer communicationsServer, INetworkManager networkManager,
+            string osName, string osVersion, bool sendOnlyMatchedHost)
         {
             if (communicationsServer == null) throw new ArgumentNullException(nameof(communicationsServer));
+            if (networkManager == null) throw new ArgumentNullException(nameof(networkManager));
             if (osName == null) throw new ArgumentNullException(nameof(osName));
             if (osName.Length == 0) throw new ArgumentException("osName cannot be an empty string.", nameof(osName));
             if (osVersion == null) throw new ArgumentNullException(nameof(osVersion));
@@ -51,10 +56,12 @@ namespace Rssdp.Infrastructure
             _RecentSearchRequests = new Dictionary<string, SearchRequest>(StringComparer.OrdinalIgnoreCase);
             _Random = new Random();
 
+            _networkManager = networkManager;
             _CommsServer = communicationsServer;
             _CommsServer.RequestReceived += CommsServer_RequestReceived;
             _OSName = osName;
             _OSVersion = osVersion;
+            _sendOnlyMatchedHost = sendOnlyMatchedHost;
 
             _CommsServer.BeginListeningForBroadcasts();
         }
@@ -250,7 +257,11 @@ namespace Rssdp.Infrastructure
 
                     foreach (var device in deviceList)
                     {
-                        SendDeviceSearchResponses(device, remoteEndPoint, receivedOnlocalIpAddress, cancellationToken);
+                        if (!_sendOnlyMatchedHost ||
+                            _networkManager.IsInSameSubnet(device.ToRootDevice().Address, remoteEndPoint.IpAddress, device.ToRootDevice().SubnetMask))
+                        {
+                            SendDeviceSearchResponses(device, remoteEndPoint, receivedOnlocalIpAddress, cancellationToken);
+                        }
                     }
                 }
                 else
@@ -427,7 +438,12 @@ namespace Rssdp.Infrastructure
 
             var message = BuildMessage(header, values);
 
-            _CommsServer.SendMulticastMessage(message, cancellationToken);
+            if (_sendOnlyMatchedHost)
+            {
+                _CommsServer.SendMulticastMessage(message, _sendOnlyMatchedHost ? rootDevice.Address : null, cancellationToken);
+            } else {
+                _CommsServer.SendMulticastMessage(message, null, cancellationToken);
+            }
 
             //WriteTrace(String.Format("Sent alive notification"), device);
         }
@@ -472,7 +488,13 @@ namespace Rssdp.Infrastructure
 
             var sendCount = IsDisposed ? 1 : 3;
             WriteTrace(String.Format("Sent byebye notification"), device);
-            return _CommsServer.SendMulticastMessage(message, sendCount, cancellationToken);
+            if (_sendOnlyMatchedHost)
+            {
+                return _CommsServer.SendMulticastMessage(message, sendCount,
+                        _sendOnlyMatchedHost ? device.ToRootDevice().Address : null, cancellationToken);
+            } else {
+                return _CommsServer.SendMulticastMessage(message, sendCount, null, cancellationToken);
+            }
         }
 
         private void DisposeRebroadcastTimer()